Rendering custom template tags from database in Django

Question

I am pretty new to Django and am trying to build a blog app for my website. I have a model I have created to store blog posts that includes a text field for the post body, created and converted to HTML using TinyMCE (via Grappelli). I would like embed custom template tags within this post body that are saved in the database as the template tag, but then rendered as HTML when requested on my site. So far, I am not having any luck getting the tags to render properly. How can I get Django to correctly interpret and render the template tags within my post? The custom tag works fine when loaded and implemented directly in a template, it is just this indirect loading that gives me trouble. I tried this snippet here (Edit: It works, I just did it wrong!), but it did not work correctly.

Here is my view:

from django.shortcuts import render_to_response
from myproject.apps.blog.models import Post

def blog_detail_view(request, year, month, day, slug):
    selected_post = Post.objects.get(status=1, pub_date__year = year, pub_date__month = time.strptime(month, "%b")[1], pub_date__day = day, slug = slug)
    return render_to_response('blog/detail.html', locals())

And the relevant portion of my template:

...
{% load my_custom_tag %}

<div class="entry">
    {{ selected_post.body|safe }}
</div>
...

Here is an example of the text saved to Post.body:

My first paragraph.
{% my_custom_tag var1 var2 %}
My second paragraph.

Currently, this will render as :

<p>My first paragraph.</p>
<p>{% my_custom_tag var1 var2 %}</p>
<p>My second paragraph.</p>

When I want something like this:

<p>My first paragraph.</p>
<p><a href="var1"><img src="var2"></a></p>
<p>My second paragraph.</p>

Answer 1

It turns out that the render_as_template tag found here DOES work, I just misunderstood it. Beginner's mistake. There are two things that were not specified in the documentation for the snippet that I failed to pick up on my own.

So, you put the render_as_template tag in your template like this:

{% load render_as_template %}
{% render_as_template myobject.attribute %}

Thus allowing any template tags within myobject.attribute to be rendered. Here is where I ran into trouble:

First, I was passing my post body to render_as_template as selected_post.body|truncatewords_html:"100"|safe or as selected_post.body|safe. The template tag is unable to process the filters on the attribute and seems to interpret them as part of the object's name. Since this object does not exist, nothing is rendered. What I need in my template is:

{% autoescape off %}
{% filter truncatewords_html:"100" %}
{% render_as_template selected_post.body %}
{% endfilter %}
{% endautoescape %}

Second, if the content of my post is:

My first paragraph.
{% my_custom_tag var1 var2 %}
My second paragraph.

Then in order for my_custom_tag to be interpreted, I need to add to my post:

{% load my_custom_tag %}

Now it works perfectly!

Answer 2

To create custom tags in Django, you need to write a tag function then register it. Link to Official Django Docs on the subject.